Detection of bacterial DNA in Latin American patients with reactive arthritis by polymerase chain reaction and sequencing analysis.

OBJECTIVE

Bacteria and/or their antigens are thought to play a role in the pathogenesis of reactive arthritis (ReA). Polymerase chain reaction (PCR) using the 16S ribosomal RNA-PCR method was used to identify bacterial DNA in synovial fluid (SF) and tissue (ST) in a well defined group of patients with chronic ReA. In addition, species found were identified by means of sequence analysis.

METHODS

We examined 15 ST and 5 SF samples of 15 patients with ReA, 5 ST samples of 5 patients with osteoarthritis (OA), and 8 SF from 8 patients with closed traumatic knee injuries using a nested PCR with universal 16S rRNA primers. In addition, a nested PCR was developed to detect DNA sequences of Salmonella sp. and Mycoplasma sp. Automated sequencing and comparative data analysis (GenBank) were also performed to identify the species.

RESULTS

Bacterial DNA was identified in 8 cases, 5 ST and 3 SF; Chlamydia trachomatis (n = 2), Pseudomonas sp. (n = 3), and Bacillus cereus (n = 2) were the most common microorganisms identified. A variety of microorganisms including Clostridium sp., Lactobacillus sp., Pseudomonas migulae, P. fluorescens, and P. putida, and Neisseria meningitidis serogroup B were also identified. In half of the cases (4/8) 2 to 3 bacterial antigens were identified simultaneously.

CONCLUSION

Bacterial DNA is present in the joints in patients with chronic ReA. A wide spectrum of bacteria including some not previously associated with ReA were identified. Further studies are needed to establish their exact role in the pathogenesis of ReA and related arthritides.